1. Field of the Invention
The present invention is directed to a pivoting crash barrier for arresting an impacting vehicle without causing excessive injury to the driver. In particular, the present invention is directed to a crash barrier having an easily replaceable expendable gate which houses multiple plastically extensible cables mounted within for absorbing the energy of the impacting vehicle.
2. Description of the Related Art
Several types of crash barriers have been patented and manufactured historically. These gates rely upon supporting plastically deformable cables between anchorages on both sides of the roadway in order to establish a readily removable and insertable barrier, which can absorb impact energy through yielding of the cables. The existing products typically sustain damage to components other than their expendable gates, such as their anchorages, during major impacts.
Furthermore, some of the existing gates, such as the gate shown in U.S. Pat. No. 4,844,653 issued to Dickinson may inadvertently permit a vehicle to escape under the cable when a low-slung vehicle imparts upward motion to the gate during an impact. The gate shown in U.S. Pat. No. 4,989,835 issued to Hirsch may inadvertently unlatch if a vehicle applies uplift during an impact.
Another problem, inherent in the design of the crash gates that are currently available, is that the gates are difficult to produce and difficult to refurbish after undergoing impact. For example, the crash gate described in U.S. Pat. Nos. 6,115,963 and 6,289,634 B1 issued to Allardyce et al. has a very complex design for interlinking the cables in an effort to cause the multiple cables of the gate to work together more or less as a unit. This complex design makes the Allardyce gate difficult to assemble. Additionally, damage to the structure other than the gate is likely, making the unit difficult to refurbish after impact.
The present invention addresses the above-mentioned deficiencies of the other designs. In particular, the present invention provides a simpler gate construction, along with means for easing service of the units and means for minimizing the likelihood of damaging structural components of the gate, other than the gate itself. Further, the present invention provides improved latching to avoid inadvertent gate uplift and unlatching in a vehicular impact.